--- /dev/null
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Copyright 2013 Alexis Laferrière <alexis.laf@xymus.net>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Supports the use of the C++ language through the FFI
+module cpp
+
+import extern_classes
+import c
+
+redef class FFILanguageAssignationPhase
+ var cpp_language: FFILanguage = new CPPLanguage(self)
+end
+
+redef class AModule
+ private var cpp_file: nullable CPPCompilationUnit = null
+end
+
+class CPPLanguage
+ super FFILanguage
+
+ redef fun identify_language(n) do return n.is_cpp
+
+ redef fun compile_module_block(block, ecc, nmodule)
+ do
+ if nmodule.cpp_file == null then nmodule.cpp_file = new CPPCompilationUnit
+
+ if block.is_cpp_header then
+ nmodule.cpp_file.header_custom.add(block.location.as_line_pragma)
+ nmodule.cpp_file.header_custom.add(block.code)
+ else if block.is_cpp_body then
+ nmodule.cpp_file.body_custom.add( block.location.as_line_pragma )
+ nmodule.cpp_file.body_custom.add( block.code )
+ end
+ end
+
+ # We call C++ from C using 2 more files (_ffi.c and _ffi.cpp) and multiple generated functions:
+ # 1. The standard C implementation function (___impl) expected by the common FFI
+ # 2. The indirection function (___cpp_impl_mid) is a C function, called from C but implemented as `extern "C"` in C++
+ # 3. The actual C++ implementation function (___cpp_impl)
+ redef fun compile_extern_method(block, m, ecc, nmodule)
+ do
+ if nmodule.cpp_file == null then nmodule.cpp_file = new CPPCompilationUnit
+
+ var mmodule = nmodule.mmodule.as(not null)
+ var mclass_type = m.parent.as(AClassdef).mclass.mclass_type
+ var mproperty = m.mpropdef.mproperty
+
+ # Signature of the indirection function implemented as `extern "C"` in C++
+ var indirection_sig = mproperty.build_csignature(mclass_type, mmodule, "___cpp_impl_mid", long_signature, internal_call_context)
+
+ ## In C file (__ffi.c)
+
+ # Declare the indirection function in C
+ ecc.body_decl.add("{indirection_sig};\n")
+
+ # Call the indirection function from C (___impl)
+ var fc: CFunction = new ExternCFunction(m, mmodule)
+ fc.exprs.add(mproperty.build_ccall(mclass_type, mmodule, "___cpp_impl_mid", long_signature, cpp_call_context, null))
+ fc.exprs.add("\n")
+ ecc.add_exported_function( fc )
+
+ ## In C++ file (__ffi.cpp)
+
+ # Declare the indirection function in C++
+ nmodule.cpp_file.header_decl.add("extern \"C\" \{\n")
+ nmodule.cpp_file.header_decl.add("{indirection_sig};\n")
+ nmodule.cpp_file.header_decl.add("\}\n")
+
+ # Implement the indirection function as extern in C++
+ # Will convert C arguments to C++ and call the C++ implementation function.
+ fc = new CFunction(indirection_sig)
+ if not mproperty.is_init then
+ var param_name = "recv"
+ var type_name = to_cpp_call_context.name_mtype(mclass_type)
+ if mclass_type.mclass.ftype isa ForeignCppType then
+ fc.exprs.add("{type_name} {param_name}_for_cpp = static_cast<{type_name}>({param_name});\n")
+ else
+ fc.exprs.add("{type_name} {param_name}_for_cpp = {param_name};\n")
+ end
+ end
+ for param in m.mpropdef.msignature.mparameters do
+ var param_name = param.name
+ var type_name = to_cpp_call_context.name_mtype(param.mtype)
+ if mclass_type.mclass.ftype isa ForeignCppType then
+ fc.exprs.add("{type_name} {param_name}_for_cpp = static_cast<{type_name}>({param_name});\n")
+ else
+ fc.exprs.add("{type_name} {param_name}_for_cpp = {param_name};\n")
+ end
+ end
+ fc.exprs.add(mproperty.build_ccall(mclass_type, mmodule, "___cpp_impl", long_signature, cpp_call_context, "_for_cpp"))
+ fc.exprs.add("\n")
+ nmodule.cpp_file.add_local_function(fc)
+
+ # Custom C++, the body of the Nit C++ method is copied to its own C++ function
+ var cpp_signature = mproperty.build_csignature(mclass_type, mmodule, "___cpp_impl", long_signature, cpp_call_context)
+ fc = new CFunction(cpp_signature)
+ fc.decls.add( block.location.as_line_pragma )
+ fc.exprs.add( block.code )
+ nmodule.cpp_file.add_local_function( fc )
+ end
+
+ redef fun compile_extern_class(block, m, ecc, nmodule) do end
+
+ redef fun get_ftype(block, m) do return new ForeignCppType(block.code)
+
+ redef fun compile_to_files(nmodule, compdir)
+ do
+ var cpp_file = nmodule.cpp_file
+ assert cpp_file != null
+
+ # write .cpp and .hpp file
+ cpp_file.header_custom.add("extern \"C\" \{\n")
+ cpp_file.header_custom.add("#include \"{nmodule.mmodule.name}._ffi.h\"\n")
+ cpp_file.header_custom.add("\}\n")
+
+ var file = cpp_file.write_to_files(nmodule, compdir)
+
+ # add complation to makefile
+ nmodule.ffi_files.add(file)
+
+ # add linked option to support C++
+ nmodule.c_linker_options = "{nmodule.c_linker_options} -lstdc++"
+ end
+
+ redef fun compile_callback(callback, nmodule, mmodule, ecc)
+ do
+ callback.compile_callback_to_cpp(nmodule, mmodule)
+ end
+end
+
+redef class AExternCodeBlock
+ fun is_cpp : Bool do return language_name != null and
+ (language_name_lowered == "c++" or language_name_lowered.has_prefix("c++ "))
+
+ fun is_cpp_body : Bool do return language_name != null and
+ (language_name_lowered == "c++" or language_name_lowered == "c++ body")
+
+ fun is_cpp_header : Bool do return language_name != null and
+ (language_name_lowered == "c++ header")
+end
+
+class CPPCompilationUnit
+ super CCompilationUnit
+
+ fun write_to_files(amodule: AModule, compdir: String): ExternCppFile
+ do
+ var base_name = "{amodule.mmodule.name}._ffi"
+
+ var h_file = "{base_name}.hpp"
+ var guard = "{amodule.cname.to_s.to_upper}_NIT_HPP"
+
+ write_header_to_file(amodule, "{compdir}/{h_file}", new Array[String], guard)
+
+ var c_file = "{base_name}.cpp"
+ write_body_to_file(amodule, "{compdir}/{c_file}", ["<string>", "<iostream>", "\"{h_file}\""])
+
+ files.add("{compdir}/{c_file}")
+
+ return new ExternCppFile("{compdir}/{c_file}")
+ end
+end
+
+class ExternCppFile
+ super ExternFile
+
+ redef fun makefile_rule_name do return "{filename.basename("")}.o"
+ redef fun makefile_rule_content do return "g++ -c {filename.basename("")} -o {filename.basename("")}.o"
+end
+
+class ForeignCppType
+ super ForeignType
+
+ var cpp_type: String
+
+ init (cpp_type: String)
+ do
+ self.cpp_type = cpp_type
+ end
+end
+
+redef class NitniCallback
+ fun compile_callback_to_cpp(nmodule: AModule, mmodule: MModule) do end
+end
+
+redef class Object
+ private fun cpp_call_context: CppCallContext do return once new CppCallContext
+ private fun to_cpp_call_context: ToCppCallContext do return once new ToCppCallContext
+ private fun from_cpp_call_context: FromCppCallContext do return once new FromCppCallContext
+end
+
+redef class MExplicitCall
+ redef fun compile_callback_to_cpp(nmodule, mmodule)
+ do
+ var mproperty = mproperty
+ assert mproperty isa MMethod
+
+ var cpp_signature = mproperty.build_csignature(recv_mtype, mmodule, null, short_signature, from_cpp_call_context)
+ var ccall = mproperty.build_ccall(recv_mtype, mmodule, null, long_signature, from_cpp_call_context, null)
+ var fc = new CFunction(cpp_signature)
+ fc.exprs.add(ccall)
+ nmodule.cpp_file.add_local_function( fc )
+ end
+end
+
+private class CppCallContext
+ super CallContext
+
+ redef fun name_mtype(mtype)
+ do
+ if mtype isa MClassType then
+ var ftype = mtype.mclass.ftype
+ if ftype isa ForeignCppType then
+ return ftype.cpp_type
+ end
+ end
+
+ return mtype.cname
+ end
+end
+
+class ToCppCallContext
+ super CppCallContext
+
+ redef fun cast_to(mtype, name)
+ do
+ if mtype isa MClassType and mtype.mclass.ftype isa ForeignCppType then
+ return "(void*)({name})"
+ else return name
+ end
+end
+
+private class FromCppCallContext
+ super CppCallContext
+
+ redef fun cast_from(mtype, name)
+ do
+ if mtype isa MClassType and mtype.mclass.ftype isa ForeignCppType then
+ return "static_cast<{name_mtype(mtype)}>({name})"
+ else return name
+ end
+end
nitlanguage / nit.git / commitdiff